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Dukembg

Nov 5 2009, 01:57 AM

Okay GMC, I need your brains here. I've been working on an online shooter, Dire Days. Currently in W.I.P. and recently I've been getting a lot of error reports with negative array indecies and game lockup.

So, when I play I'm usually hosting and I never get errors... ever.... however players join.. play... and randomly run into errors...

ERRORS : (ALL Happen when a player leaves or joins a game)

CODE

ERROR in
action number 1
of Step Event
for object obj_game_controller:

In script scr_player:
Error in code at line 44:
global.playersname[a] = soc_receive(global.host,SOC_STRING,b);

at position 37: Negative array index

CODE

ERROR in
action number 1
of Step Event
for object obj_game_controller:

In script scr_player:
Error in code at line 56:
if(global.playersin[a] != 0){

at position 28: Unknown variable playersin or array index out of bounds

CODE

ERROR in
action number 1
of Step Event
for object obj_game_controller:

In script scr_player:
Error in code at line 51:
global.playersname[a] = soc_receive(global.host,SOC_STRING,b);

at position 37: Negative array index

HOST SCRIPT: (Host sends the variable "n" which the player receives and uses in an array index... n is never below 0 and never higher than 30)
When a player joins the game :

CODE

120 - if(datatype == 33){
121 -                 a = soc_receive(global.players[n],SOC_SHORT);
122 -                 global.playersname[n] = soc_receive(global.players[n],SOC_STRING,a);
123 -                 scr_add_message(global.playersname[n]+" has joined the game.",c_red);
124 -                obj_game_controller.host_sync_player = true;
125 -                 obj_game_controller.host_sync_timer = 0;
126 -                 obj_game_controller.host_sync_id = n;
127 -                 global.buffer = buffer_create();
128 -                 buffer_add(global.buffer,SOC_BYTE,32);
129 -                 buffer_add(global.buffer,SOC_SHORT,obj_game_controller.ga
metimemilli);
130 -                 buffer_add(global.buffer,SOC_SHORT,obj_game_controller.ga
metimesec);
131 -                 buffer_add(global.buffer,SOC_SHORT,obj_game_controller.ga
metimemin);
132 -                 buffer_add(global.buffer,SOC_SHORT,obj_game_controller.al
lyscore);
133 -                 buffer_add(global.buffer,SOC_SHORT,obj_game_controller.ax
isscore);
134 -                 soc_send(global.players[n],global.buffer);
135 -                 buffer_destroy(global.buffer);
136 -                 global.buffer = buffer_create();
137 -                 buffer_add(global.buffer,SOC_BYTE,33);
138 -                 buffer_add(global.buffer,SOC_SHORT,n);
139 -                 buffer_add(global.buffer,SOC_SHORT,string_length(global.playersname[n]));
140 -                 buffer_add(global.buffer,SOC_STRING,string_length(global.playersname[n]),global.playersname[n]);
141 -                 for(m=0; m<31; m+=1){
142 -                     if(soc_valid(global.players[m]) and m != n){
143 -                         soc_send(global.players[m],global.buffer);
144 -                    }
145 -                 }
146 -                 buffer_destroy(global.buffer);
147 -             }

When a player leaves a game :

CODE

26 - if not(soc_valid(global.players[n])){
27 -             global.numberofplayers-=1;
28 -             obj_game_controller.player_clear_mine = true;
29 -             obj_game_controller.player_clear_timer = 0;
30 -             obj_game_controller.player_clear_id = n;
31 -             global.buffer = buffer_create();
32 -             buffer_add(global.buffer,SOC_BYTE,34);
33 -             buffer_add(global.buffer,SOC_SHORT,n);
34 -             buffer_add(global.buffer,SOC_SHORT,string_length(global.playersname[n]));
35 -            buffer_add(global.buffer,SOC_STRING,string_length(global.playersname[n]),global.playersname[n]);
36 -             for(m=0; m<31; m+=1){
37 -                 if(soc_valid(global.players[m]) and m != n){
38 -                     soc_send(global.players[m],global.buffer);
39 -                 }
40 -             }
41 -             buffer_destroy(global.buffer);
42 -             scr_add_message(global.playersname[n]+" has left the game.",c_red);
43 -             if(global.playersin[n] != 0){
44 -                 global.playersin[n].destroy = true;
45 -             }
46 -             global.playersin[n] = 0;
47 -             global.playersname[n] = "";
48 -             global.playersteam[n] = 0;
49 -             soc_destroy(global.players[n]);
50 -             global.players[n] = 0;
51 -             global.buffer = buffer_create();
52 -             buffer_add(global.buffer,SOC_BYTE,6);
53 -             buffer_add(global.buffer,SOC_SHORT,global.numberofplayers);
54 -             soc_send(global.server,global.buffer);
55 -             buffer_destroy(global.buffer);
56 -             continue;
57 -         }

PLAYER SCRIPT: (WHERE THE ERRORS ARE: "a" is the variable receiving what host sent as "n")
receiving player joined :

CODE

41 - if(datatype == 33){
42 -                 a = soc_receive(global.host,SOC_SHORT);
43 -                 b = soc_receive(global.host,SOC_SHORT);
44 -                 global.playersname[a] = soc_receive(global.host,SOC_STRING,b);
45 -                 global.players[a] = 1;
46 -                 scr_add_message(global.playersname[a]+" has joined the game.",c_red);
47 -             }

receiving player left :

CODE

48 - if(datatype == 34){
49 -                 a = soc_receive(global.host,SOC_SHORT);
50 -                 b = soc_receive(global.host,SOC_SHORT);
51 -                 global.playersname[a] = soc_receive(global.host,SOC_STRING,b);
52 -                 scr_add_message(global.playersname[a]+" has left the game.",c_red);
53 -                 obj_game_controller.player_clear_mine = true;
54 -                 obj_game_controller.player_clear_timer = 0;
55 -                 obj_game_controller.player_clear_id = a;
56 -                 if(global.playersin[a] != 0){
57 -                     global.playersin[a].destroy = true;
58 -                 }
59 -                 global.playersin[a] = 0;
60 -                 global.playersname[a] = "";
61 -                 global.playersteam[a] = 0;
62 -                 global.players[a] = 0;
63 -             }

johnjoe

Nov 5 2009, 09:40 AM

you should create the instance [player] after the data is recieved, otherwise it'll cause confusion for the computer. because it takes time to send all those neccessary information for your player, delays are inevitable, therefore whilst the client is being delayed of recieving those information it 4ses any sort of value available for player's id which is in this case is the error - a negative array.

the client connects to the server. if the client is connected, send its id. once the client receives its id from the server, create the instance player and assign the id received to the instance, or better yet set the id as a global variable value. otherwise disconnect the client for the reason that either the server is full, or the client is not connected, instead of throwing error 'negative array' due to it being delayed and using the default array value.

i've dealt with the problem multiple times. and my fixes are most likely similar to that.

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